
<!DOCTYPE HTML>
<html lang="" >
    <head>
        <meta charset="UTF-8">
        <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
        <title>leveldb源码分析21 · 高性能服务器开发 技术专栏</title>
        <meta http-equiv="X-UA-Compatible" content="IE=edge" />
        <meta name="description" content="">
        <meta name="generator" content="GitBook 3.2.3">
        <meta name="author" content="easy_coder">
        
        
    
    <link rel="stylesheet" href="../../gitbook/style.css">

    
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-chapter-fold/chapter-fold.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-search-pro/search.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-splitter/splitter.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-back-to-top-button/plugin.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-prism/prism.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-tbfed-pagefooter/footer.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-code/plugin.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-anchor-navigation-ex/style/plugin.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-fontsettings/website.css">
                
            
                
                <link rel="stylesheet" href="../../gitbook/gitbook-plugin-theme-fexa/fexa.css">
                
            
        

    

    
        
    
        
    
        
    
        
    
        
    
        
    

        
    
    
    <meta name="HandheldFriendly" content="true"/>
    <meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no">
    <meta name="apple-mobile-web-app-capable" content="yes">
    <meta name="apple-mobile-web-app-status-bar-style" content="black">
    <link rel="apple-touch-icon-precomposed" sizes="152x152" href="../../gitbook/images/apple-touch-icon-precomposed-152.png">
    <link rel="shortcut icon" href="../../gitbook/images/favicon.ico" type="image/x-icon">

    
    <link rel="next" href="leveldb源码分析22.html" />
    
    
    <link rel="prev" href="leveldb源码分析20.html" />
    

    </head>
    <body>
        
<div class="book">
	<div class="header-inner">
		<!-- LOGO -->
		<div class="logo"></div>
		<span class="title"></span>

		<!-- Search -->
		
<div id="book-search-input" role="search">
    <input type="text" placeholder="Type to search" />
</div>


		<!-- Nav -->
		<ul class="header-nav">
			
		</ul>
	</div>

	<div class="book-summary">
		<div class="book-summary-title">文档目录</div>
		
		
		<nav role="navigation">
			


<ul class="summary">
    
    

    

    
        
        <li class="header">Part I</li>
        
        
    
        <li class="chapter " data-level="1.1" data-path="../../">
            
                <a href="../../">
            
                    
                    Introduction
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2" data-path="../C++必知必会的知识点/">
            
                <a href="../C++必知必会的知识点/">
            
                    
                    C++必知必会的知识点
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.2.1" data-path="../C++必知必会的知识点/如何成为一名合格的CC++开发者？.html">
            
                <a href="../C++必知必会的知识点/如何成为一名合格的CC++开发者？.html">
            
                    
                    如何成为一名合格的C/C++开发者？
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.2" data-path="../C++必知必会的知识点/不定参数函数实现var_arg系列的宏.html">
            
                <a href="../C++必知必会的知识点/不定参数函数实现var_arg系列的宏.html">
            
                    
                    不定参数函数实现var_arg系列的宏
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.3" data-path="../C++必知必会的知识点/你一定要搞明白的C函数调用方式与栈原理.html">
            
                <a href="../C++必知必会的知识点/你一定要搞明白的C函数调用方式与栈原理.html">
            
                    
                    你一定要搞明白的C函数调用方式与栈原理
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.4" data-path="../C++必知必会的知识点/深入理解CC++中的指针.html">
            
                <a href="../C++必知必会的知识点/深入理解CC++中的指针.html">
            
                    
                    深入理解C/C++中的指针
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.5" data-path="../C++必知必会的知识点/详解C++11中的智能指针.html">
            
                <a href="../C++必知必会的知识点/详解C++11中的智能指针.html">
            
                    
                    详解C++11中的智能指针
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.6" data-path="../C++必知必会的知识点/C++17结构化绑定.html">
            
                <a href="../C++必知必会的知识点/C++17结构化绑定.html">
            
                    
                    C++17结构化绑定
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.7" data-path="../C++必知必会的知识点/C++必须掌握的pimpl惯用法.html">
            
                <a href="../C++必知必会的知识点/C++必须掌握的pimpl惯用法.html">
            
                    
                    C++必须掌握的pimpl惯用法
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.8" data-path="../C++必知必会的知识点/用VisualStudio调试Linux程序.html">
            
                <a href="../C++必知必会的知识点/用VisualStudio调试Linux程序.html">
            
                    
                    用Visual Studio调试Linux程序
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.9" data-path="../C++必知必会的知识点/如何使用VisualStudio管理和阅读开源项目代码.html">
            
                <a href="../C++必知必会的知识点/如何使用VisualStudio管理和阅读开源项目代码.html">
            
                    
                    如何使用Visual Studio管理和阅读开源项目代码
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.2.10" data-path="../C++必知必会的知识点/利用cmake工具生成VisualStudio工程文件.html">
            
                <a href="../C++必知必会的知识点/利用cmake工具生成VisualStudio工程文件.html">
            
                    
                    利用cmake工具生成Visual Studio工程文件
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="1.3" data-path="../多线程/">
            
                <a href="../多线程/">
            
                    
                    多线程
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="1.3.1" data-path="../多线程/后台C++开发你一定要知道的条件变量.html">
            
                <a href="../多线程/后台C++开发你一定要知道的条件变量.html">
            
                    
                    后台C++开发你一定要知道的条件变量
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="1.3.2" data-path="../多线程/整型变量赋值是原子操作吗？.html">
            
                <a href="../多线程/整型变量赋值是原子操作吗？.html">
            
                    
                    整型变量赋值是原子操作吗？
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="divider"></li>
        
        
    
        <li class="chapter " data-level="2.1" data-path="../网络编程/">
            
                <a href="../网络编程/">
            
                    
                    网络编程
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="2.1.1" data-path="../网络编程/bind函数重难点解析.html">
            
                <a href="../网络编程/bind函数重难点解析.html">
            
                    
                    bind 函数重难点解析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.2" data-path="../网络编程/connect函数在阻塞和非阻塞模式下的行为.html">
            
                <a href="../网络编程/connect函数在阻塞和非阻塞模式下的行为.html">
            
                    
                    connect 函数在阻塞和非阻塞模式下的行为
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.3" data-path="../网络编程/select函数重难点解析.html">
            
                <a href="../网络编程/select函数重难点解析.html">
            
                    
                    select 函数重难点解析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.4" data-path="../网络编程/Linuxepoll模型（含LT模式和ET模式详解）.html">
            
                <a href="../网络编程/Linuxepoll模型（含LT模式和ET模式详解）.html">
            
                    
                    Linux epoll 模型（含LT 模式和 ET 模式详解）
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.5" data-path="../网络编程/socket的阻塞模式和非阻塞模式.html">
            
                <a href="../网络编程/socket的阻塞模式和非阻塞模式.html">
            
                    
                    socket 的阻塞模式和非阻塞模式
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.6" data-path="../网络编程/非阻塞模式下send和recv函数的返回值.html">
            
                <a href="../网络编程/非阻塞模式下send和recv函数的返回值.html">
            
                    
                    非阻塞模式下 send 和 recv 函数的返回值
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.7" data-path="../网络编程/服务器开发通信协议设计介绍.html">
            
                <a href="../网络编程/服务器开发通信协议设计介绍.html">
            
                    
                    服务器开发通信协议设计介绍
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.8" data-path="../网络编程/TCP协议如何解决粘包、半包问题.html">
            
                <a href="../网络编程/TCP协议如何解决粘包、半包问题.html">
            
                    
                    TCP 协议如何解决粘包、半包问题
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.9" data-path="../网络编程/网络通信中收发数据的正确姿势.html">
            
                <a href="../网络编程/网络通信中收发数据的正确姿势.html">
            
                    
                    网络通信中收发数据的正确姿势
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.1.10" data-path="../网络编程/服务器端发数据时，如果对端一直不收，怎么办？.html">
            
                <a href="../网络编程/服务器端发数据时，如果对端一直不收，怎么办？.html">
            
                    
                    服务器端发数据时，如果对端一直不收，怎么办？
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="divider"></li>
        
        
    
        <li class="chapter " data-level="3.1" data-path="../程序员必知必会的网络命令/">
            
                <a href="../程序员必知必会的网络命令/">
            
                    
                    程序员必知必会的网络命令
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="3.1.1" data-path="../程序员必知必会的网络命令/利用telnet命令发电子邮件.html">
            
                <a href="../程序员必知必会的网络命令/利用telnet命令发电子邮件.html">
            
                    
                    利用telnet命令发电子邮件
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.1.2" data-path="../程序员必知必会的网络命令/做Java或者C++开发都应该知道的lsof命令.html">
            
                <a href="../程序员必知必会的网络命令/做Java或者C++开发都应该知道的lsof命令.html">
            
                    
                    做Java或者C++开发都应该知道的lsof命令
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.1.3" data-path="../程序员必知必会的网络命令/Linux网络故障排查的瑞士军刀.html">
            
                <a href="../程序员必知必会的网络命令/Linux网络故障排查的瑞士军刀.html">
            
                    
                    Linux网络故障排查的瑞士军刀nc命令
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.1.4" data-path="../程序员必知必会的网络命令/Linuxtcpdump使用介绍.html">
            
                <a href="../程序员必知必会的网络命令/Linuxtcpdump使用介绍.html">
            
                    
                    Linux tcpdump使用详解
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.1.5" data-path="../程序员必知必会的网络命令/从抓包的角度分析connect函数的连接过程.html">
            
                <a href="../程序员必知必会的网络命令/从抓包的角度分析connect函数的连接过程.html">
            
                    
                    从抓包的角度分析connect函数的连接过程
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="3.1.6" data-path="../程序员必知必会的网络命令/服务器开发中网络数据分析与故障排查经验漫谈.html">
            
                <a href="../程序员必知必会的网络命令/服务器开发中网络数据分析与故障排查经验漫谈.html">
            
                    
                    服务器开发中网络数据分析与故障排查经验漫谈
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">Part II</li>
        
        
    
        <li class="chapter " data-level="4.1" data-path="../高性能服务器框架设计/">
            
                <a href="../高性能服务器框架设计/">
            
                    
                    高性能服务器框架设计
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="4.1.1" data-path="../高性能服务器框架设计/主线程与工作线程的分工.html">
            
                <a href="../高性能服务器框架设计/主线程与工作线程的分工.html">
            
                    
                    主线程与工作线程的分工
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.2" data-path="../高性能服务器框架设计/Reactor模式.html">
            
                <a href="../高性能服务器框架设计/Reactor模式.html">
            
                    
                    Reactor模式
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.3" data-path="../高性能服务器框架设计/实例：一个服务器程序的架构介绍.html">
            
                <a href="../高性能服务器框架设计/实例：一个服务器程序的架构介绍.html">
            
                    
                    实例：一个服务器程序的架构介绍
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.4" data-path="../高性能服务器框架设计/错误码系统的设计.html">
            
                <a href="../高性能服务器框架设计/错误码系统的设计.html">
            
                    
                    错误码系统的设计
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.5" data-path="../高性能服务器框架设计/日志系统的设计.html">
            
                <a href="../高性能服务器框架设计/日志系统的设计.html">
            
                    
                    日志系统的设计
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.6" data-path="../高性能服务器框架设计/如何设计断线自动重连机制.html">
            
                <a href="../高性能服务器框架设计/如何设计断线自动重连机制.html">
            
                    
                    如何设计断线自动重连机制
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.7" data-path="../高性能服务器框架设计/心跳包机制设计详解.html">
            
                <a href="../高性能服务器框架设计/心跳包机制设计详解.html">
            
                    
                    心跳包机制设计详解
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.8" data-path="../高性能服务器框架设计/业务数据处理一定要单独开线程吗.html">
            
                <a href="../高性能服务器框架设计/业务数据处理一定要单独开线程吗.html">
            
                    
                    业务数据处理一定要单独开线程吗
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="4.1.9" data-path="../高性能服务器框架设计/C++高性能服务器网络框架设计细节.html">
            
                <a href="../高性能服务器框架设计/C++高性能服务器网络框架设计细节.html">
            
                    
                    C++ 高性能服务器网络框架设计细节
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="divider"></li>
        
        
    
        <li class="chapter " data-level="5.1" data-path="../服务器开发案例实战/">
            
                <a href="../服务器开发案例实战/">
            
                    
                    服务器开发案例实战
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="5.1.1" data-path="../服务器开发案例实战/从零实现一个http服务器.html">
            
                <a href="../服务器开发案例实战/从零实现一个http服务器.html">
            
                    
                    从零实现一个http服务器
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.1.2" data-path="../服务器开发案例实战/从零实现一款12306刷票软件.html">
            
                <a href="../服务器开发案例实战/从零实现一款12306刷票软件.html">
            
                    
                    从零实现一款12306刷票软件
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.1.3" data-path="../服务器开发案例实战/从零实现一个邮件收发客户端.html">
            
                <a href="../服务器开发案例实战/从零实现一个邮件收发客户端.html">
            
                    
                    从零实现一个邮件收发客户端
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.1.4" data-path="../服务器开发案例实战/从零开发一个WebSocket服务器.html">
            
                <a href="../服务器开发案例实战/从零开发一个WebSocket服务器.html">
            
                    
                    从零开发一个WebSocket服务器
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.1.5" data-path="../服务器开发案例实战/1从一款多人联机实时对战游戏开始.html">
            
                <a href="../服务器开发案例实战/1从一款多人联机实时对战游戏开始.html">
            
                    
                    从零学习开源项目系列（一） 从一款多人联机实时对战游戏开始
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.1.6" data-path="../服务器开发案例实战/2最后一战概况.html">
            
                <a href="../服务器开发案例实战/2最后一战概况.html">
            
                    
                    从零学习开源项目系列（二） 最后一战概况
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.1.7" data-path="../服务器开发案例实战/3CSBattleMgr服务源码研究.html">
            
                <a href="../服务器开发案例实战/3CSBattleMgr服务源码研究.html">
            
                    
                    从零学习开源项目系列（三） CSBattleMgr服务源码研究
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="5.1.8" data-path="../服务器开发案例实战/4LogServer源码探究.html">
            
                <a href="../服务器开发案例实战/4LogServer源码探究.html">
            
                    
                    从零学习开源项目系列（四）LogServer源码探究
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">Part III</li>
        
        
    
        <li class="chapter " data-level="6.1" data-path="../TeamTalk源码解析/">
            
                <a href="../TeamTalk源码解析/">
            
                    
                    TeamTalk IM源码分析
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="6.1.1" data-path="../TeamTalk源码解析/01TeamTalk介绍.html">
            
                <a href="../TeamTalk源码解析/01TeamTalk介绍.html">
            
                    
                    01 TeamTalk介绍
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.2" data-path="../TeamTalk源码解析/02服务器端的程序的编译与部署.html">
            
                <a href="../TeamTalk源码解析/02服务器端的程序的编译与部署.html">
            
                    
                    02 服务器端的程序的编译与部署
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.3" data-path="../TeamTalk源码解析/03服务器端的程序架构介绍.html">
            
                <a href="../TeamTalk源码解析/03服务器端的程序架构介绍.html">
            
                    
                    03 服务器端的程序架构介绍
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.4" data-path="../TeamTalk源码解析/04服务器端db_proxy_server源码分析.html">
            
                <a href="../TeamTalk源码解析/04服务器端db_proxy_server源码分析.html">
            
                    
                    04 服务器端db_proxy_server源码分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.5" data-path="../TeamTalk源码解析/05服务器端msg_server源码分析.html">
            
                <a href="../TeamTalk源码解析/05服务器端msg_server源码分析.html">
            
                    
                    05 服务器端msg_server源码分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.6" data-path="../TeamTalk源码解析/06服务器端login_server源码分析.html">
            
                <a href="../TeamTalk源码解析/06服务器端login_server源码分析.html">
            
                    
                    06 服务器端login_server源码分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.7" data-path="../TeamTalk源码解析/07服务器端msfs源码分析.html">
            
                <a href="../TeamTalk源码解析/07服务器端msfs源码分析.html">
            
                    
                    07 服务器端msfs源码分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.8" data-path="../TeamTalk源码解析/08服务器端file_server源码分析.html">
            
                <a href="../TeamTalk源码解析/08服务器端file_server源码分析.html">
            
                    
                    08 服务器端file_server源码分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.9" data-path="../TeamTalk源码解析/09服务器端route_server源码分析.html">
            
                <a href="../TeamTalk源码解析/09服务器端route_server源码分析.html">
            
                    
                    09 服务器端route_server源码分析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.10" data-path="../TeamTalk源码解析/10开放一个TeamTalk测试服务器地址和几个测试账号.html">
            
                <a href="../TeamTalk源码解析/10开放一个TeamTalk测试服务器地址和几个测试账号.html">
            
                    
                    10 开放一个TeamTalk测试服务器地址和几个测试账号
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="6.1.11" data-path="../TeamTalk源码解析/11pc客户端源码分析.html">
            
                <a href="../TeamTalk源码解析/11pc客户端源码分析.html">
            
                    
                    11 pc客户端源码分析
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="divider"></li>
        
        
    
        <li class="chapter " data-level="7.1" data-path="../libevent源码深度剖析/">
            
                <a href="../libevent源码深度剖析/">
            
                    
                    libevent源码深度剖析
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="7.1.1" data-path="../libevent源码深度剖析/libevent源码深度剖析01.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析01.html">
            
                    
                    libevent源码深度剖析01
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.2" data-path="../libevent源码深度剖析/libevent源码深度剖析02.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析02.html">
            
                    
                    libevent源码深度剖析02
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.3" data-path="../libevent源码深度剖析/libevent源码深度剖析03.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析03.html">
            
                    
                    libevent源码深度剖析03
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.4" data-path="../libevent源码深度剖析/libevent源码深度剖析04.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析04.html">
            
                    
                    libevent源码深度剖析04
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.5" data-path="../libevent源码深度剖析/libevent源码深度剖析05.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析05.html">
            
                    
                    libevent源码深度剖析05
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.6" data-path="../libevent源码深度剖析/libevent源码深度剖析06.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析06.html">
            
                    
                    libevent源码深度剖析06
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.7" data-path="../libevent源码深度剖析/libevent源码深度剖析07.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析07.html">
            
                    
                    libevent源码深度剖析07
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.8" data-path="../libevent源码深度剖析/libevent源码深度剖析08.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析08.html">
            
                    
                    libevent源码深度剖析08
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.9" data-path="../libevent源码深度剖析/libevent源码深度剖析09.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析09.html">
            
                    
                    libevent源码深度剖析09
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.10" data-path="../libevent源码深度剖析/libevent源码深度剖析10.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析10.html">
            
                    
                    libevent源码深度剖析10
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.11" data-path="../libevent源码深度剖析/libevent源码深度剖析11.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析11.html">
            
                    
                    libevent源码深度剖析11
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.12" data-path="../libevent源码深度剖析/libevent源码深度剖析12.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析12.html">
            
                    
                    libevent源码深度剖析12
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.1.13" data-path="../libevent源码深度剖析/libevent源码深度剖析13.html">
            
                <a href="../libevent源码深度剖析/libevent源码深度剖析13.html">
            
                    
                    libevent源码深度剖析13
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="7.2" data-path="./">
            
                <a href="./">
            
                    
                    leveldb源码分析
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="7.2.1" data-path="leveldb源码分析1.html">
            
                <a href="leveldb源码分析1.html">
            
                    
                    leveldb源码分析1
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.2" data-path="leveldb源码分析2.html">
            
                <a href="leveldb源码分析2.html">
            
                    
                    leveldb源码分析2
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.3" data-path="leveldb源码分析3.html">
            
                <a href="leveldb源码分析3.html">
            
                    
                    leveldb源码分析3
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.4" data-path="leveldb源码分析4.html">
            
                <a href="leveldb源码分析4.html">
            
                    
                    leveldb源码分析4
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.5" data-path="leveldb源码分析5.html">
            
                <a href="leveldb源码分析5.html">
            
                    
                    leveldb源码分析5
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.6" data-path="leveldb源码分析6.html">
            
                <a href="leveldb源码分析6.html">
            
                    
                    leveldb源码分析6
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.7" data-path="leveldb源码分析7.html">
            
                <a href="leveldb源码分析7.html">
            
                    
                    leveldb源码分析7
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.8" data-path="leveldb源码分析8.html">
            
                <a href="leveldb源码分析8.html">
            
                    
                    leveldb源码分析8
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.9" data-path="leveldb源码分析9.html">
            
                <a href="leveldb源码分析9.html">
            
                    
                    leveldb源码分析9
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.10" data-path="leveldb源码分析10.html">
            
                <a href="leveldb源码分析10.html">
            
                    
                    leveldb源码分析10
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.11" data-path="leveldb源码分析11.html">
            
                <a href="leveldb源码分析11.html">
            
                    
                    leveldb源码分析11
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.12" data-path="leveldb源码分析12.html">
            
                <a href="leveldb源码分析12.html">
            
                    
                    leveldb源码分析12
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.13" data-path="leveldb源码分析13.html">
            
                <a href="leveldb源码分析13.html">
            
                    
                    leveldb源码分析13
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.14" data-path="leveldb源码分析14.html">
            
                <a href="leveldb源码分析14.html">
            
                    
                    leveldb源码分析14
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.15" data-path="leveldb源码分析15.html">
            
                <a href="leveldb源码分析15.html">
            
                    
                    leveldb源码分析15
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.16" data-path="leveldb源码分析16.html">
            
                <a href="leveldb源码分析16.html">
            
                    
                    leveldb源码分析16
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.17" data-path="leveldb源码分析17.html">
            
                <a href="leveldb源码分析17.html">
            
                    
                    leveldb源码分析17
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.18" data-path="leveldb源码分析18.html">
            
                <a href="leveldb源码分析18.html">
            
                    
                    leveldb源码分析18
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.19" data-path="leveldb源码分析19.html">
            
                <a href="leveldb源码分析19.html">
            
                    
                    leveldb源码分析19
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.20" data-path="leveldb源码分析20.html">
            
                <a href="leveldb源码分析20.html">
            
                    
                    leveldb源码分析20
            
                </a>
            

            
        </li>
    
        <li class="chapter active" data-level="7.2.21" data-path="leveldb源码分析21.html">
            
                <a href="leveldb源码分析21.html">
            
                    
                    leveldb源码分析21
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="7.2.22" data-path="leveldb源码分析22.html">
            
                <a href="leveldb源码分析22.html">
            
                    
                    leveldb源码分析22
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="divider"></li>
        
        
    
        <li class="chapter " data-level="8.1" data-path="../Memcached源码分析/">
            
                <a href="../Memcached源码分析/">
            
                    
                    Memcached源码分析
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="8.1.1" data-path="../Memcached源码分析/00服务器资源调整.html">
            
                <a href="../Memcached源码分析/00服务器资源调整.html">
            
                    
                    00 服务器资源调整
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.2" data-path="../Memcached源码分析/01初始化参数解析.html">
            
                <a href="../Memcached源码分析/01初始化参数解析.html">
            
                    
                    01 初始化参数解析
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.3" data-path="../Memcached源码分析/02网络监听的建立.html">
            
                <a href="../Memcached源码分析/02网络监听的建立.html">
            
                    
                    02 网络监听的建立
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.4" data-path="../Memcached源码分析/03网络连接建立.html">
            
                <a href="../Memcached源码分析/03网络连接建立.html">
            
                    
                    03 网络连接建立
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.5" data-path="../Memcached源码分析/04内存初始化.html">
            
                <a href="../Memcached源码分析/04内存初始化.html">
            
                    
                    04 内存初始化
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.6" data-path="../Memcached源码分析/05资源初始化.html">
            
                <a href="../Memcached源码分析/05资源初始化.html">
            
                    
                    05 资源初始化
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.7" data-path="../Memcached源码分析/06get过程.html">
            
                <a href="../Memcached源码分析/06get过程.html">
            
                    
                    06 get过程
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.8" data-path="../Memcached源码分析/07cas属性.html">
            
                <a href="../Memcached源码分析/07cas属性.html">
            
                    
                    07 cas属性
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.9" data-path="../Memcached源码分析/08内存池.html">
            
                <a href="../Memcached源码分析/08内存池.html">
            
                    
                    08 内存池
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.10" data-path="../Memcached源码分析/09连接队列.html">
            
                <a href="../Memcached源码分析/09连接队列.html">
            
                    
                    09 连接队列
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.11" data-path="../Memcached源码分析/10Hash表操作.html">
            
                <a href="../Memcached源码分析/10Hash表操作.html">
            
                    
                    10 Hash表操作
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.12" data-path="../Memcached源码分析/12set操作.html">
            
                <a href="../Memcached源码分析/12set操作.html">
            
                    
                    12 set操作
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.13" data-path="../Memcached源码分析/13do_item_alloc操作.html">
            
                <a href="../Memcached源码分析/13do_item_alloc操作.html">
            
                    
                    13 do_item_alloc操作
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.14" data-path="../Memcached源码分析/14item结构.html">
            
                <a href="../Memcached源码分析/14item结构.html">
            
                    
                    14 item结构
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.15" data-path="../Memcached源码分析/15Hash表扩容.html">
            
                <a href="../Memcached源码分析/15Hash表扩容.html">
            
                    
                    15 Hash表扩容
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.16" data-path="../Memcached源码分析/16线程交互.html">
            
                <a href="../Memcached源码分析/16线程交互.html">
            
                    
                    16 线程交互
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="8.1.17" data-path="../Memcached源码分析/17状态机.html">
            
                <a href="../Memcached源码分析/17状态机.html">
            
                    
                    17 状态机
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="divider"></li>
        
        
    
        <li class="chapter " data-level="9.1" data-path="../游戏开发专题/">
            
                <a href="../游戏开发专题/">
            
                    
                    游戏开发专题
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="9.1.1" data-path="../游戏开发专题/1游戏服务器开发的基本体系与服务器端开发的一些建议.html">
            
                <a href="../游戏开发专题/1游戏服务器开发的基本体系与服务器端开发的一些建议.html">
            
                    
                    1 游戏服务器开发的基本体系与服务器端开发的一些建议
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.2" data-path="../游戏开发专题/2网络游戏服务器开发框架设计介绍.html">
            
                <a href="../游戏开发专题/2网络游戏服务器开发框架设计介绍.html">
            
                    
                    2 网络游戏服务器开发框架设计介绍
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.3" data-path="../游戏开发专题/3游戏后端开发需要掌握的知识.html">
            
                <a href="../游戏开发专题/3游戏后端开发需要掌握的知识.html">
            
                    
                    3 游戏后端开发需要掌握的知识
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.4" data-path="../游戏开发专题/4关于游戏服务端架构的整理.html">
            
                <a href="../游戏开发专题/4关于游戏服务端架构的整理.html">
            
                    
                    4 关于游戏服务端架构的整理
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.5" data-path="../游戏开发专题/5各类游戏对应的服务端架构.html">
            
                <a href="../游戏开发专题/5各类游戏对应的服务端架构.html">
            
                    
                    5 各类游戏对应的服务端架构
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.6" data-path="../游戏开发专题/6从腾讯QQgame高性能服务器集群架构看“分而治之”与“自治”等分布式架构设计原则.html">
            
                <a href="../游戏开发专题/6从腾讯QQgame高性能服务器集群架构看“分而治之”与“自治”等分布式架构设计原则.html">
            
                    
                    6 从腾讯QQgame高性能服务器集群架构看“分而治之”与“自治”等分布式架构设计原则
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.7" data-path="../游戏开发专题/7QQ游戏百万人同时在线服务器架构实现.html">
            
                <a href="../游戏开发专题/7QQ游戏百万人同时在线服务器架构实现.html">
            
                    
                    7 QQ游戏百万人同时在线服务器架构实现
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.8" data-path="../游戏开发专题/8大型多人在线游戏服务器架构设计.html">
            
                <a href="../游戏开发专题/8大型多人在线游戏服务器架构设计.html">
            
                    
                    8 大型多人在线游戏服务器架构设计
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.9" data-path="../游戏开发专题/9百万用户级游戏服务器架构设计.html">
            
                <a href="../游戏开发专题/9百万用户级游戏服务器架构设计.html">
            
                    
                    9 百万用户级游戏服务器架构设计
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.10" data-path="../游戏开发专题/10十万在线的WebGame的数据库设计思路.html">
            
                <a href="../游戏开发专题/10十万在线的WebGame的数据库设计思路.html">
            
                    
                    10 十万在线的WebGame的数据库设计思路
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.11" data-path="../游戏开发专题/11一种高性能网络游戏服务器架构设计.html">
            
                <a href="../游戏开发专题/11一种高性能网络游戏服务器架构设计.html">
            
                    
                    11 一种高性能网络游戏服务器架构设计
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.12" data-path="../游戏开发专题/12经典游戏服务器端架构概述.html">
            
                <a href="../游戏开发专题/12经典游戏服务器端架构概述.html">
            
                    
                    12 经典游戏服务器端架构概述
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="9.1.13" data-path="../游戏开发专题/13游戏跨服架构进化之路.html">
            
                <a href="../游戏开发专题/13游戏跨服架构进化之路.html">
            
                    
                    13 游戏跨服架构进化之路
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    
        
        <li class="header">Part IV</li>
        
        
    
        <li class="chapter " data-level="10.1" data-path="../程序员面试题精讲/">
            
                <a href="../程序员面试题精讲/">
            
                    
                    程序员面试题精讲
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="10.1.1" data-path="../程序员面试题精讲/腾讯后台开发实习生技能要求.html">
            
                <a href="../程序员面试题精讲/腾讯后台开发实习生技能要求.html">
            
                    
                    腾讯后台开发实习生技能要求
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="10.1.2" data-path="../程序员面试题精讲/聊聊如何拿大厂的offer.html">
            
                <a href="../程序员面试题精讲/聊聊如何拿大厂的offer.html">
            
                    
                    聊聊如何拿大厂的 offer
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="10.1.3" data-path="../程序员面试题精讲/网络通信题目集锦.html">
            
                <a href="../程序员面试题精讲/网络通信题目集锦.html">
            
                    
                    网络通信题目集锦
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="10.1.4" data-path="../程序员面试题精讲/我面试后端开发经理的经历.html">
            
                <a href="../程序员面试题精讲/我面试后端开发经理的经历.html">
            
                    
                    我面试后端开发经理的经历
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="10.1.5" data-path="../程序员面试题精讲/LinuxCC++后端开发面试问哪些问题.html">
            
                <a href="../程序员面试题精讲/LinuxCC++后端开发面试问哪些问题.html">
            
                    
                    Linux C/C++后端开发面试问哪些问题
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="10.2" data-path="../职业规划/">
            
                <a href="../职业规划/">
            
                    
                    职业规划
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="10.2.1" data-path="../职业规划/给工作4年迷茫的程序员们的一点建议.html">
            
                <a href="../职业规划/给工作4年迷茫的程序员们的一点建议.html">
            
                    
                    给工作 4 年迷茫的程序员们的一点建议
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="10.2.2" data-path="../职业规划/聊聊技术人员的常见的职业问题.html">
            
                <a href="../职业规划/聊聊技术人员的常见的职业问题.html">
            
                    
                    聊聊技术人员的常见的职业问题
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="10.2.3" data-path="../职业规划/写给那些傻傻想做服务器开发的朋友.html">
            
                <a href="../职业规划/写给那些傻傻想做服务器开发的朋友.html">
            
                    
                    写给那些傻傻想做服务器开发的朋友
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="10.3" data-path="../自我提升与开源代码/">
            
                <a href="../自我提升与开源代码/">
            
                    
                    自我提升与开源代码
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="10.3.1" data-path="../自我提升与开源代码/2020年好好读一读开源代码吧.html">
            
                <a href="../自我提升与开源代码/2020年好好读一读开源代码吧.html">
            
                    
                    2020 年好好读一读开源代码吧
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="10.4" data-path="../后端开发相关的书籍/">
            
                <a href="../后端开发相关的书籍/">
            
                    
                    后端开发相关的书籍
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="10.4.1" data-path="../后端开发相关的书籍/后台开发应该读的书.html">
            
                <a href="../后端开发相关的书籍/后台开发应该读的书.html">
            
                    
                    后台开发应该读的书
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="10.5" data-path="../程序员的简历/">
            
                <a href="../程序员的简历/">
            
                    
                    程序员的简历
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="10.5.1" data-path="../程序员的简历/程序员如何写简历.html">
            
                <a href="../程序员的简历/程序员如何写简历.html">
            
                    
                    程序员如何写简历
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="10.6" data-path="../程序员的薪资与年终奖那些事儿/">
            
                <a href="../程序员的薪资与年终奖那些事儿/">
            
                    
                    程序员的薪资与年终奖那些事儿
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="10.6.1" data-path="../程序员的薪资与年终奖那些事儿/技术面试与HR谈薪资技巧.html">
            
                <a href="../程序员的薪资与年终奖那些事儿/技术面试与HR谈薪资技巧.html">
            
                    
                    技术面试与HR谈薪资技巧
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="10.6.2" data-path="../程序员的薪资与年终奖那些事儿/聊一聊程序员如何增加收入.html">
            
                <a href="../程序员的薪资与年终奖那些事儿/聊一聊程序员如何增加收入.html">
            
                    
                    聊一聊程序员如何增加收入
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="10.6.3" data-path="../程序员的薪资与年终奖那些事儿/谈一谈年终奖.html">
            
                <a href="../程序员的薪资与年终奖那些事儿/谈一谈年终奖.html">
            
                    
                    谈一谈年终奖
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="10.7" data-path="../程序员的烦心事/">
            
                <a href="../程序员的烦心事/">
            
                    
                    程序员的烦心事
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="10.7.1" data-path="../程序员的烦心事/拒绝了一家公司的offer后，他们的副总和hr总监同时打电话来询问拒绝原因并极力要求加入，我该不该去？.html">
            
                <a href="../程序员的烦心事/拒绝了一家公司的offer后，他们的副总和hr总监同时打电话来询问拒绝原因并极力要求加入，我该不该去？.html">
            
                    
                    拒绝了一家公司的offer后，他们的副总和hr总监同时打电话来询问拒绝原因并极力要求加入，我该不该去？
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="10.7.2" data-path="../程序员的烦心事/我是一名程序员，结婚时女友要求我用两年的工资作为彩礼，我该不该答应？.html">
            
                <a href="../程序员的烦心事/我是一名程序员，结婚时女友要求我用两年的工资作为彩礼，我该不该答应？.html">
            
                    
                    我是一名程序员，结婚时女友要求我用两年的工资作为彩礼，我该不该答应？
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="10.8" data-path="../作者的故事/">
            
                <a href="../作者的故事/">
            
                    
                    作者的故事
            
                </a>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="10.8.1" data-path="../作者的故事/我的2019.html">
            
                <a href="../作者的故事/我的2019.html">
            
                    
                    我的 2019
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="10.8.2" data-path="../作者的故事/我是如何年薪五十万的.html">
            
                <a href="../作者的故事/我是如何年薪五十万的.html">
            
                    
                    我是如何年薪五十万的
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    

    

    <li class="divider"></li>

    <li>
        <a href="https://www.gitbook.com" target="blank" class="gitbook-link">
            Published with GitBook
        </a>
    </li>
</ul>


		</nav>
		
		
	</div>

	<!-- Content nav -->
	<div class="book-anchor">
		<div class="book-anchor-title">在这篇文章中:</div>
		<div class="book-anchor-body">

		</div>
	</div>

	<div class="book-body">
		
		<div class="body-inner">
			
			

<div class="book-header" role="navigation">
    

    <!-- Title -->
    <h1>
        <i class="fa fa-circle-o-notch fa-spin"></i>
        <a href="../.." >leveldb源码分析21</a>
    </h1>
</div>




			<div class="page-wrapper" tabindex="-1" role="main">
				<div class="page-inner">
					
<div id="book-search-results">
    <div class="search-noresults">
    
					<section class="normal markdown-section">
						
						<div id="anchor-navigation-ex-navbar"><i class="fa fa-navicon"></i><ul><li><span class="title-icon "></span><a href="#leveldb&#x6E90;&#x7801;&#x5206;&#x6790;21"><b></b>leveldb&#x6E90;&#x7801;&#x5206;&#x6790;21</a></li><ul><li><span class="title-icon "></span><a href="#14-db&#x7684;&#x67E5;&#x8BE2;&#x4E0E;&#x904D;&#x5386;&#x4E4B;1"><b></b>14 DB&#x7684;&#x67E5;&#x8BE2;&#x4E0E;&#x904D;&#x5386;&#x4E4B;1</a></li><ul><li><span class="title-icon "></span><a href="#141-get"><b></b>14.1 Get()</a></li><li><span class="title-icon "></span><a href="#142-newiterator"><b></b>14.2 NewIterator()</a></li><li><span class="title-icon "></span><a href="#143-mergingiterator"><b></b>14.3 MergingIterator</a></li></ul></ul></ul></div><h1 id="leveldb&#x6E90;&#x7801;&#x5206;&#x6790;21"><a name="leveldb&#x6E90;&#x7801;&#x5206;&#x6790;21" class="anchor-navigation-ex-anchor" href="#leveldb&#x6E90;&#x7801;&#x5206;&#x6790;21"><i class="fa fa-link" aria-hidden="true"></i></a>leveldb&#x6E90;&#x7801;&#x5206;&#x6790;21</h1>
<p>&#x672C;&#x7CFB;&#x5217;&#x300A;leveldb&#x6E90;&#x7801;&#x5206;&#x6790;&#x300B;&#x5171;&#x6709;22&#x7BC7;&#x6587;&#x7AE0;&#xFF0C;&#x8FD9;&#x662F;&#x7B2C;&#x4E8C;&#x5341;&#x4E00;&#x7BC7;</p>
<h2 id="14-db&#x7684;&#x67E5;&#x8BE2;&#x4E0E;&#x904D;&#x5386;&#x4E4B;1"><a name="14-db&#x7684;&#x67E5;&#x8BE2;&#x4E0E;&#x904D;&#x5386;&#x4E4B;1" class="anchor-navigation-ex-anchor" href="#14-db&#x7684;&#x67E5;&#x8BE2;&#x4E0E;&#x904D;&#x5386;&#x4E4B;1"><i class="fa fa-link" aria-hidden="true"></i></a>14 DB&#x7684;&#x67E5;&#x8BE2;&#x4E0E;&#x904D;&#x5386;&#x4E4B;1</h2>
<p>&#x5206;&#x6790;&#x5B8C;&#x5982;&#x4F55;&#x6253;&#x5F00;&#x548C;&#x5173;&#x95ED;db&#xFF0C;&#x672C;&#x7AE0;&#x5C31;&#x7EE7;&#x7EED;&#x5206;&#x6790;&#x5982;&#x4F55;<strong>&#x4ECE;db&#x4E2D;&#x6839;&#x636E;key&#x67E5;&#x8BE2;value</strong>&#xFF0C;&#x4EE5;&#x53CA;<strong>&#x904D;&#x5386;&#x6574;&#x4E2A;db</strong>&#x3002;</p>
<h3 id="141-get"><a name="141-get" class="anchor-navigation-ex-anchor" href="#141-get"><i class="fa fa-link" aria-hidden="true"></i></a>14.1 Get()</h3>
<p>&#x51FD;&#x6570;&#x58F0;&#x660E;&#xFF1A;<strong>StatusGet(const ReadOptions&amp; options, const Slice&amp; key, std::string* value)</strong>
&#x4ECE;DB&#x4E2D;&#x67E5;&#x8BE2;key &#x5BF9;&#x5E94;&#x7684;value&#xFF0C;&#x53C2;&#x6570;@options&#x6307;&#x5B9A;&#x8BFB;&#x53D6;&#x64CD;&#x4F5C;&#x7684;&#x9009;&#x9879;&#xFF0C;&#x5178;&#x578B;&#x7684;&#x5982;snapshot&#x53F7;&#xFF0C;&#x4ECE;&#x6307;&#x5B9A;&#x7684;&#x5FEB;&#x7167;&#x4E2D;&#x8BFB;&#x53D6;&#x3002;&#x5FEB;&#x7167;&#x672C;&#x8D28;&#x4E0A;&#x5C31;&#x662F;&#x4E00;&#x4E2A;sequence&#x53F7;&#xFF0C;&#x540E;&#x9762;&#x5C06;&#x5355;&#x72EC;&#x5728;&#x5FEB;&#x7167;&#x4E00;&#x7AE0;&#x4E2D;&#x5206;&#x6790;&#x3002;
&#x4E0B;&#x9762;&#x5C31;&#x6765;&#x5206;&#x6790;&#x4E0B;&#x51FD;&#x6570;&#x903B;&#x8F91;&#xFF1A;</p>
<pre class="language-"><code>// S1 &#x9501;mutex&#xFF0C;&#x9632;&#x6B62;&#x5E76;&#x53D1;&#xFF0C;&#x5982;&#x679C;&#x6307;&#x5B9A;option&#x5219;&#x5C1D;&#x8BD5;&#x83B7;&#x53D6;snapshot&#xFF1B;&#x7136;&#x540E;&#x589E;&#x52A0;MemTable&#x7684;&#x5F15;&#x7528;&#x503C;&#x3002;  
MutexLock l(&amp;mutex_);
SequenceNumber snapshot;
if (options.snapshot != NULL)
snapshot = reinterpret_cast<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>const</span> <span class="token attr-name">SnapshotImpl*</span><span class="token punctuation">&gt;</span></span>(options.snapshot)-&gt;number_;
else snapshot = versions_-&gt;LastSequence(); // &#x53D6;&#x5F53;&#x524D;&#x7248;&#x672C;&#x7684;&#x6700;&#x540E;Sequence  
MemTable *mem = mem_, *imm = imm_;
Version* current = versions_-&gt;current();
mem-&gt;Ref();
if (imm != NULL) imm-&gt;Ref();
current-&gt;Ref();
// S2 &#x4ECE;sstable&#x6587;&#x4EF6;&#x548C;MemTable&#x4E2D;&#x8BFB;&#x53D6;&#x65F6;&#xFF0C;&#x91CA;&#x653E;&#x9501;mutex&#xFF1B;&#x4E4B;&#x540E;&#x518D;&#x6B21;&#x9501;mutex&#x3002;  
bool have_stat_update = false;
Version::GetStats stats;
{
    mutex_.Unlock();
    // &#x5148;&#x4ECE;memtable&#x4E2D;&#x67E5;&#x8BE2;&#xFF0C;&#x518D;&#x4ECE;immutable memtable&#x4E2D;&#x67E5;&#x8BE2;  
    LookupKey lkey(key, snapshot);
    if (mem-&gt;Get(lkey, value, &amp;s)) {
    }
    else if (imm != NULL &amp;&amp; imm-&gt;Get(lkey, value, &amp;s)) {
    }
    else { // &#x9700;&#x8981;&#x4ECE;sstable&#x6587;&#x4EF6;&#x4E2D;&#x67E5;&#x8BE2;  
        s = current-&gt;Get(options, lkey, value, &amp;stats);
        have_stat_update = true; // &#x8BB0;&#x5F55;&#x4E4B;&#xFF0C;&#x7528;&#x4E8E;compaction  
    }
    mutex_.Lock();
}
// S3 &#x5982;&#x679C;&#x662F;&#x4ECE;sstable&#x6587;&#x4EF6;&#x67E5;&#x8BE2;&#x51FA;&#x6765;&#x7684;&#xFF0C;&#x68C0;&#x67E5;&#x662F;&#x5426;&#x9700;&#x8981;&#x505A;compaction&#x3002;&#x6700;&#x540E;&#x628A;MemTable&#x7684;&#x5F15;&#x7528;&#x8BA1;&#x6570;&#x51CF;1&#x3002;  
if (have_stat_update &amp;&#xA4;t-&gt;UpdateStats(stats)) {
    MaybeScheduleCompaction();
}
mem-&gt;Unref();
if (imm != NULL)imm-&gt;Unref();
current-&gt;Unref();
</code></pre><p>&#x67E5;&#x8BE2;&#x662F;&#x6BD4;&#x8F83;&#x7B80;&#x5355;&#x7684;&#x64CD;&#x4F5C;&#xFF0C;UpdateStats&#x5728;&#x524D;&#x9762;Version&#x4E00;&#x8282;&#x5DF2;&#x7ECF;&#x5206;&#x6790;&#x8FC7;&#x3002;</p>
<h3 id="142-newiterator"><a name="142-newiterator" class="anchor-navigation-ex-anchor" href="#142-newiterator"><i class="fa fa-link" aria-hidden="true"></i></a>14.2 NewIterator()</h3>
<p>&#x51FD;&#x6570;&#x58F0;&#x660E;&#xFF1A;<strong>Iterator*NewIterator(const ReadOptions&amp; options)</strong>
&#x901A;&#x8FC7;&#x8BE5;&#x51FD;&#x6570;&#x751F;&#x4EA7;&#x4E86;&#x4E00;&#x4E2A;Iterator<em>&#x5BF9;&#x8C61;&#xFF0C;&#x8C03;&#x7528;&#x8FD9;&#x5C31;&#x53EF;&#x4EE5;&#x57FA;&#x4E8E;&#x8BE5;&#x5BF9;&#x8C61;&#x904D;&#x5386;db&#x5185;&#x5BB9;&#x4E86;&#x3002;
&#x51FD;&#x6570;&#x5F88;&#x7B80;&#x5355;&#xFF0C;&#x8C03;&#x7528;&#x4E24;&#x4E2A;&#x51FD;&#x6570;&#x521B;&#x5EFA;&#x4E86;&#x4E00;&#x4E2A;&#x4E8C;&#x7EA7;<em>*Iterator</em></em>&#x3002;</p>
<pre class="language-"><code>Iterator* DBImpl::NewIterator(const ReadOptions&amp; options) {
    SequenceNumber latest_snapshot;
    Iterator* internal_iter = NewInternalIterator(options, &amp;latest_snapshot);
    returnNewDBIterator(&amp;dbname_, env_, user_comparator(), internal_iter,
        (options.snapshot != NULL
            ? reinterpret_cast<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>constSnapshotImpl*</span><span class="token punctuation">&gt;</span></span>(options.snapshot)-&gt;number_
            : latest_snapshot));
}
</code></pre><p>&#x5176;&#x4E2D;&#xFF0C;&#x51FD;&#x6570;NewDBIterator&#x76F4;&#x63A5;&#x8FD4;&#x56DE;&#x4E86;&#x4E00;&#x4E2A;<strong>DBIter</strong>&#x6307;&#x9488;</p>
<pre class="language-"><code>Iterator* NewDBIterator(const std::string* dbname, Env* env,
    const Comparator*user_key_comparator, Iterator* internal_iter,
    const SequenceNumber&amp; sequence) {
    return new DBIter(dbname, env, user_key_comparator, internal_iter, sequence);
}
</code></pre><p>&#x51FD;&#x6570;NewInternalIterator&#x6709;&#x4E00;&#x4E9B;&#x5904;&#x7406;&#x903B;&#x8F91;&#xFF0C;&#x5C31;&#x662F;&#x6536;&#x96C6;&#x6240;&#x6709;&#x80FD;&#x7528;&#x5230;&#x7684;iterator&#xFF0C;&#x751F;&#x4EA7;&#x4E00;&#x4E2A;Merging Iterator&#x3002;&#x8FD9;&#x5305;&#x62EC;MemTable&#xFF0C;Immutable MemTable&#xFF0C;&#x4EE5;&#x53CA;&#x5404;sstable&#x3002;</p>
<pre class="language-"><code>Iterator* DBImpl::NewInternalIterator(const ReadOptions&amp; options,
    SequenceNumber*latest_snapshot) {
    IterState* cleanup = newIterState;
    mutex_.Lock();
    // &#x6839;&#x636E;last sequence&#x8BBE;&#x7F6E;lastest snapshot&#xFF0C;&#x5E76;&#x6536;&#x96C6;&#x6240;&#x6709;&#x7684;&#x5B50;iterator  
    *latest_snapshot = versions_-&gt;LastSequence();
    std::vector<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>Iterator*</span><span class="token punctuation">&gt;</span></span>list;
    list.push_back(mem_-&gt;NewIterator()); // &gt;memtable  
    mem_-&gt;Ref();
    if (imm_ != NULL) {
        list.push_back(imm_-&gt;NewIterator()); // &gt;immutablememtable  
        imm_-&gt;Ref();
    }
    versions_-&gt;current()-&gt;AddIterators(options, &amp;list); // &gt;current&#x7684;&#x6240;&#x6709;sstable  
    Iterator* internal_iter = NewMergingIterator(&amp;internal_comparator_, &amp;list[0], list.size());
    versions_-&gt;current()-&gt;Ref();
    // &#x6CE8;&#x518C;&#x6E05;&#x7406;&#x673A;&#x5236;  
    cleanup-&gt;mu = &amp;mutex_;
    cleanup-&gt;mem = mem_;
    cleanup-&gt;imm = imm_;
    cleanup-&gt;version = versions_-&gt;current();
    internal_iter-&gt;RegisterCleanup(CleanupIteratorState, cleanup, NULL);
    mutex_.Unlock();
    return internal_iter;
}
</code></pre><p>&#x8FD9;&#x4E2A;&#x6E05;&#x7406;&#x51FD;&#x6570;CleanupIteratorState&#x662F;&#x5F88;&#x7B80;&#x5355;&#x7684;&#xFF0C;&#x5BF9;&#x6CE8;&#x518C;&#x7684;&#x5BF9;&#x8C61;&#x505A;&#x4E00;&#x4E0B;Unref&#x64CD;&#x4F5C;&#x5373;&#x53EF;&#x3002;</p>
<pre class="language-"><code>static void CleanupIteratorState(void* arg1, void* arg2) {
    IterState* state = reinterpret_cast<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>IterState*</span><span class="token punctuation">&gt;</span></span>(arg1);
    state-&gt;mu-&gt;Lock();
    state-&gt;mem-&gt;Unref();
    if (state-&gt;imm != NULL)state-&gt;imm-&gt;Unref();
    state-&gt;version-&gt;Unref();
    state-&gt;mu-&gt;Unlock();
    delete state;
}
</code></pre><p>&#x53EF;&#x89C1;&#x5BF9;&#x4E8E;db&#x7684;&#x904D;&#x5386;&#x4F9D;&#x8D56;&#x4E8E;DBIter&#x548C;Merging Iterator&#x8FD9;&#x4E24;&#x4E2A;&#x8FED;&#x4EE3;&#x5668;&#xFF0C;&#x5B83;&#x4EEC;&#x90FD;&#x662F;Iterator&#x63A5;&#x53E3;&#x7684;&#x5B9E;&#x73B0;&#x5B50;&#x7C7B;&#x3002;</p>
<h3 id="143-mergingiterator"><a name="143-mergingiterator" class="anchor-navigation-ex-anchor" href="#143-mergingiterator"><i class="fa fa-link" aria-hidden="true"></i></a>14.3 MergingIterator</h3>
<p>MergingIterator&#x662F;&#x4E00;&#x4E2A;&#x5408;&#x5E76;&#x8FED;&#x4EE3;&#x5668;&#xFF0C;&#x5B83;&#x5185;&#x90E8;&#x4F7F;&#x7528;&#x4E86;&#x4E00;&#x7EC4;&#x81EA;Iterator&#xFF0C;&#x4FDD;&#x5B58;&#x5728;&#x5176;&#x6210;&#x5458;&#x6570;&#x7EC4;children_&#x4E2D;&#x3002;&#x5982;&#x4E0A;&#x9762;&#x7684;&#x51FD;&#x6570;NewInternalIterator&#xFF0C;&#x5305;&#x62EC;memtable&#xFF0C;immutable memtable&#xFF0C;&#x4EE5;&#x53CA;&#x5404;sstable&#x6587;&#x4EF6;&#xFF1B;&#x5B83;&#x6240;&#x505A;&#x7684;&#x5C31;&#x662F;&#x6839;&#x636E;&#x8C03;&#x7528;&#x8005;&#x6307;&#x5B9A;&#x7684;key&#x548C;sequence&#xFF0C;&#x4ECE;&#x8FD9;&#x4E9B;Iterator&#x4E2D;&#x627E;&#x5230;&#x5408;&#x9002;&#x7684;&#x8BB0;&#x5F55;&#x3002;
&#x5728;&#x5206;&#x6790;&#x5176;Iterator&#x63A5;&#x53E3;&#x4E4B;&#x524D;&#xFF0C;&#x5148;&#x6765;&#x770B;&#x770B;&#x4E24;&#x4E2A;&#x8F85;&#x52A9;&#x51FD;&#x6570;FindSmallest&#x548C;FindLargest&#x3002;FindSmallest<strong>&#x4ECE;0&#x5F00;&#x59CB;&#x5411;&#x540E;&#x904D;&#x5386;&#x5185;&#x90E8;Iterator&#x6570;&#x7EC4;</strong>&#xFF0C;&#x627E;&#x5230;key&#x6700;&#x5C0F;&#x7684;Iterator&#xFF0C;&#x5E76;&#x8BBE;&#x7F6E;&#x5230;current<em>&#xFF1B;FindLargest&#x4ECE;<strong>&#x6700;&#x540E;&#x4E00;&#x4E2A;&#x5411;&#x524D;&#x904D;&#x5386;&#x5185;&#x90E8;Iterator&#x6570;&#x7EC4;</strong>&#xFF0C;&#x627E;&#x5230;key&#x6700;&#x5927;&#x7684;Iterator&#xFF0C;&#x5E76;&#x8BBE;&#x7F6E;&#x5230;current</em>&#xFF1B;
MergingIterator&#x8FD8;&#x5B9A;&#x4E49;&#x4E86;&#x4E24;&#x4E2A;&#x79FB;&#x52A8;&#x65B9;&#x5411;&#xFF1A;kForward&#xFF0C;&#x5411;&#x524D;&#x79FB;&#x52A8;&#xFF1B;kReverse&#xFF0C;&#x5411;&#x540E;&#x79FB;&#x52A8;&#x3002; </p>
<h4 id="1431-get&#x7CFB;&#x63A5;&#x53E3;"><a name="1431-get&#x7CFB;&#x63A5;&#x53E3;" class="anchor-navigation-ex-anchor" href="#1431-get&#x7CFB;&#x63A5;&#x53E3;"><i class="fa fa-link" aria-hidden="true"></i></a>14.3.1 Get&#x7CFB;&#x63A5;&#x53E3;</h4>
<p>&#x4E0B;&#x9762;&#x5C31;&#x628A;&#x5176;&#x63A5;&#x53E3;&#x62D6;&#x51FA;&#x6765;&#x4E00;&#x4E2A;&#x4E00;&#x4E2A;&#x5206;&#x6790;&#xFF0C;&#x9996;&#x5148;&#x662F;&#x7B80;&#x5355;&#x63A5;&#x53E3;&#xFF0C;key&#x548C;value&#x90FD;&#x662F;&#x8FD4;&#x56DE;current<em>&#x7684;&#x503C;&#xFF0C;current</em>&#x662F;&#x5F53;&#x524D;seek&#x5230;&#x7684;Iterator&#x4F4D;&#x7F6E;&#x3002;</p>
<pre class="language-"><code>virtual Slice key() const {
    assert(Valid());
    return current_-&gt;key();
}

virtual Slice value() const {
    assert(Valid());
    return current_-&gt;value();
}

virtual Status status() const {
    Status status;
    for (int i = 0; i &lt; n_; i++) { // &#x53EA;&#x6709;&#x6240;&#x6709;&#x5185;&#x90E8;Iterator&#x90FD;ok&#x65F6;&#xFF0C;&#x624D;&#x8FD4;&#x56DE;ok  
        status = children_[i].status();
        if (!status.ok()) break;
    }
    return status;
}
</code></pre><h4 id="1432-seek&#x7CFB;&#x63A5;&#x53E3;"><a name="1432-seek&#x7CFB;&#x63A5;&#x53E3;" class="anchor-navigation-ex-anchor" href="#1432-seek&#x7CFB;&#x63A5;&#x53E3;"><i class="fa fa-link" aria-hidden="true"></i></a>14.3.2 Seek&#x7CFB;&#x63A5;&#x53E3;</h4>
<p>&#x7136;&#x540E;&#x662F;&#x51E0;&#x4E2A;seek&#x7CFB;&#x7684;&#x51FD;&#x6570;&#xFF0C;&#x4E5F;&#x6BD4;&#x8F83;&#x7B80;&#x5355;&#xFF0C;&#x90FD;&#x662F;&#x4F9D;&#x6B21;&#x8C03;&#x7528;&#x5185;&#x90E8;Iterator&#x7684;seek&#x7CFB;&#x51FD;&#x6570;&#x3002;&#x7136;&#x540E;&#x505A;merge&#xFF0C;&#x5BF9;&#x4E8E;Seek&#x548C;SeekToFirst&#x90FD;&#x8C03;&#x7528;FindSmallest&#xFF1B;&#x5BF9;&#x4E8E;SeekToLast&#x8C03;&#x7528;FindLargest&#x3002;</p>
<pre class="language-"><code>virtual void SeekToFirst() {
    for (int i = 0; i &lt; n_; i++) children_[i].SeekToFirst();
    FindSmallest();
    direction_ = kForward;
}

virtual void SeekToLast() {
    for (int i = 0; i &lt; n_; i++) children_[i].SeekToLast();
    FindLargest();
    direction_ = kReverse;
}

virtual void Seek(constSlice&amp; target) {
    for (int i = 0; i &lt; n_; i++) children_[i].Seek(target);
    FindSmallest();
    direction_ = kForward;
}
</code></pre><h4 id="1433-&#x9010;&#x6B65;&#x79FB;&#x52A8;"><a name="1433-&#x9010;&#x6B65;&#x79FB;&#x52A8;" class="anchor-navigation-ex-anchor" href="#1433-&#x9010;&#x6B65;&#x79FB;&#x52A8;"><i class="fa fa-link" aria-hidden="true"></i></a>14.3.3 &#x9010;&#x6B65;&#x79FB;&#x52A8;</h4>
<p>&#x6700;&#x540E;&#x5C31;&#x662F;Next&#x548C;Prev&#x51FD;&#x6570;&#xFF0C;&#x5B8C;&#x6210;&#x8FED;&#x4EE3;&#x904D;&#x5386;&#x3002;&#x8FD9;&#x53EF;&#x80FD;&#x4F1A;&#x6709;&#x70B9;&#x7ED5;&#x3002;&#x4E0B;&#x9762;&#x5206;&#x522B;&#x6765;&#x8BF4;&#x660E;&#x3002;
&#x9996;&#x5148;&#xFF0C;&#x5728;Next&#x79FB;&#x52A8;&#x65F6;&#xFF0C;&#x5982;&#x679C;&#x5F53;&#x524D;direction&#x4E0D;&#x662F;kForward&#x7684;&#xFF0C;&#x4E5F;&#x5C31;&#x662F;&#x4E0A;&#x4E00;&#x6B21;&#x8C03;&#x7528;&#x4E86;Prev&#x6216;&#x8005;SeekToLast&#x51FD;&#x6570;&#xFF0C;&#x5C31;&#x9700;&#x8981;&#x5148;&#x8C03;&#x6574;&#x9664;current&#x4E4B;&#x5916;&#x7684;&#x6240;&#x6709;iterator&#xFF0C;&#x4E3A;&#x4EC0;&#x4E48;&#x8981;&#x505A;&#x8FD9;&#x79CD;&#x8C03;&#x6574;&#x5462;&#xFF1F;&#x5570;&#x55E6;&#x4E00;&#x70B9;&#xFF0C;&#x8003;&#x8651;&#x5982;&#x4E0B;&#x7684;&#x573A;&#x666F;&#xFF0C;&#x5982;&#x56FE;14.3-1&#x6240;&#x793A;&#x3002;</p>
<p><img src="../imgs/leveldb19.webp" alt=""></p>
<p>&#x56FE;14.3-1 Next&#x7684;&#x79FB;&#x52A8;</p>
<p>&#x5F53;&#x524D;direction&#x4E3A;kReverse&#xFF0C;&#x5E76;&#x4E14;&#x6709;&#xFF1A;<strong>Current = memtable Iterator</strong>&#x3002;&#x5404;Iterator&#x4F4D;&#x7F6E;&#x4E3A;&#xFF1A;{memtable, stable 0, sstable1} ={ key3:1:1, key2:3:1, key2:1:1}&#xFF0C;&#x8FD9;&#x7B26;&#x5408;prev&#x64CD;&#x4F5C;&#x7684;largest key&#x8981;&#x6C42;&#x3002;
&#x6CE8;&#xFF1A;&#x9700;&#x8981;&#x8BF4;&#x660E;&#x4E0B;&#xFF0C;&#x5BF9;&#x4E8E;&#x6BCF;&#x4E2A;update&#x64CD;&#x4F5C;&#xFF0C;leveldb&#x90FD;&#x4F1A;&#x8D4B;&#x4E88;&#x4E00;&#x4E2A;&#x5168;&#x5C40;&#x552F;&#x4E00;&#x7684;sequence&#x53F7;&#xFF0C;&#x4E14;&#x662F;&#x9012;&#x589E;&#x7684;&#x3002;&#x4F8B;&#x5B50;&#x4E2D;&#x7684;sequence&#x53F7;&#x53EF;&#x7406;&#x89E3;&#x4E3A;&#x6BCF;&#x4E2A;key&#x7684;&#x76F8;&#x5BF9;&#x503C;&#xFF0C;&#x540E;&#x9762;&#x4E5F;&#x662F;&#x5982;&#x6B64;&#x3002;
&#x63A5;&#x4E0B;&#x6765;&#x6211;&#x4EEC;&#x6765;&#x5206;&#x6790;Prev&#x79FB;&#x52A8;&#x7684;&#x64CD;&#x4F5C;&#x3002;
&#x7B2C;&#x4E00;&#x6B21;Prev&#xFF0C;current(memtable iterator)&#x79FB;&#x52A8;&#x5230;key1:3:0&#x4E0A;&#xFF0C;3&#x8005;&#x4E2D;&#x6700;&#x5927;&#x8005;&#x53D8;&#x6210;sstable0&#xFF1B;&#x56E0;&#x6B64;current&#x4FEE;&#x6539;&#x4E3A;sstable0&#xFF1B;
&#x7B2C;&#x4E8C;&#x6B21;Prev&#xFF0C;current(sstable0 Iterator)&#x79FB;&#x52A8;&#x5230;key1:2:1&#x4E0A;&#xFF0C;3&#x8005;&#x4E2D;&#x6700;&#x5927;&#x8005;&#x53D8;&#x6210;sstable1&#xFF1B;&#x56E0;&#x6B64;current&#x4FEE;&#x6539;&#x4E3A;sstable1:
&#x6B64;&#x65F6;&#x5404;Iterator&#x7684;&#x4F4D;&#x7F6E;&#x4E3A;{memtable, sstable 0, sstable1} = { key1:3:0, key1:2:1, key2:2:1}&#xFF0C;&#x5E76;&#x4E14;current=sstable1&#x3002;
&#x63A5;&#x4E0B;&#x6765;&#x518D;&#x8C03;&#x7528;Next&#xFF0C;&#x663E;&#x7136;&#x5F53;&#x524D;Key()&#x4E3A;key2:2:1&#xFF0C;&#x7EFC;&#x5408;&#x8003;&#x8651;3&#x4E2A;iterator&#xFF0C;&#x4E24;&#x6B21;Next()&#x7684;&#x8C03;&#x7528;&#x7ED3;&#x679C;&#x5E94;&#x8BE5;&#x662F;key2:1:1&#x548C;key3:1:1&#x3002;&#x800C;memtable&#x548C;sstable0&#x6307;&#x5411;&#x7684;key&#x5374;&#x662F;key1:3:0&#x548C;key1:2:1&#xFF0C;&#x8FD9;&#x65F6;&#x5C31;&#x9700;&#x8981;&#x8C03;&#x6574;memtable&#x548C;sstable0&#x4E86;&#xFF0C;&#x4F7F;&#x4ED6;&#x4EEC;&#x90FD;&#x5B9A;&#x4F4D;&#x5230;Key()&#x4E4B;&#x540E;&#xFF0C;&#x4E5F;&#x5C31;&#x662F;key3:1:1&#x548C;key2:3:1&#x4E0A;&#x3002;
&#x7136;&#x540E;current(current1)Next&#x79FB;&#x52A8;&#x5230;key2:1:1&#x4E0A;&#x3002;&#x8FD9;&#x5C31;&#x662F;Next&#x65F6;&#x7684;&#x8C03;&#x6574;&#x903B;&#x8F91;&#xFF0C;&#x540C;&#x7406;&#xFF0C;&#x5BF9;&#x4E8E;Prev&#x4E5F;&#x6709;&#x76F8;&#x540C;&#x7684;&#x8C03;&#x6574;&#x903B;&#x8F91;&#x3002;&#x4EE3;&#x7801;&#x5982;&#x4E0B;&#xFF1A;</p>
<pre class="language-"><code>virtual void Next() {
    assert(Valid());
    // &#x786E;&#x4FDD;&#x6240;&#x6709;&#x7684;&#x5B50;Iterator&#x90FD;&#x5B9A;&#x4F4D;&#x5728;key()&#x4E4B;&#x540E;.  
    // &#x5982;&#x679C;&#x6211;&#x4EEC;&#x5728;&#x6B63;&#x5411;&#x79FB;&#x52A8;&#xFF0C;&#x5BF9;&#x4E8E;&#x9664;current_&#x5916;&#x7684;&#x6240;&#x6709;&#x5B50;Iterator&#x8FD9;&#x70B9;&#x5DF2;&#x7136;&#x6210;&#x7ACB;  
    // &#x56E0;&#x4E3A;current_&#x662F;&#x6700;&#x5C0F;&#x7684;&#x5B50;Iterator&#xFF0C;&#x5E76;&#x4E14;key() = current_-&gt;key()&#x3002;  
    // &#x5426;&#x5219;&#xFF0C;&#x6211;&#x4EEC;&#x9700;&#x8981;&#x660E;&#x786E;&#x8BBE;&#x7F6E;&#x5176;&#x5B83;&#x7684;&#x5B50;Iterator  
    if (direction_ != kForward) {
        for (int i = 0; i &lt; n_; i++) { // &#x628A;&#x6240;&#x6709;current&#x4E4B;&#x5916;&#x7684;Iterator&#x5B9A;&#x4F4D;&#x5230;key()&#x4E4B;&#x540E;  
            IteratorWrapper* child = &amp;children_[i];
            if (child != current_) {
                child-&gt;Seek(key());
                if (child-&gt;Valid() &amp;&amp; comparator_-&gt;Compare(key(), child-&gt;key()) == 0)
                    child-&gt;Next(); // key&#x7B49;&#x4E8E;current_-&gt;key()&#x7684;&#xFF0C;&#x518D;&#x5411;&#x540E;&#x79FB;&#x52A8;&#x4E00;&#x4F4D;  
            }
        }
        direction_ = kForward;
    }
    // current&#x4E5F;&#x5411;&#x540E;&#x79FB;&#x4E00;&#x4F4D;&#xFF0C;&#x7136;&#x540E;&#x518D;&#x67E5;&#x627E;key&#x6700;&#x5C0F;&#x7684;Iterator  
    current_-&gt;Next();
    FindSmallest();
}

virtual void Prev() {
    assert(Valid());
    // &#x786E;&#x4FDD;&#x6240;&#x6709;&#x7684;&#x5B50;Iterator&#x90FD;&#x5B9A;&#x4F4D;&#x5728;key()&#x4E4B;&#x524D;.  
    // &#x5982;&#x679C;&#x6211;&#x4EEC;&#x5728;&#x9006;&#x5411;&#x79FB;&#x52A8;&#xFF0C;&#x5BF9;&#x4E8E;&#x9664;current_&#x5916;&#x7684;&#x6240;&#x6709;&#x5B50;Iterator&#x8FD9;&#x70B9;&#x5DF2;&#x7136;&#x6210;&#x7ACB;  
    // &#x56E0;&#x4E3A;current_&#x662F;&#x6700;&#x5927;&#x7684;&#xFF0C;&#x5E76;&#x4E14;key() = current_-&gt;key()  
    // &#x5426;&#x5219;&#xFF0C;&#x6211;&#x4EEC;&#x9700;&#x8981;&#x660E;&#x786E;&#x8BBE;&#x7F6E;&#x5176;&#x5B83;&#x7684;&#x5B50;Iterator  
    if (direction_ != kReverse) {
        for (int i = 0; i &lt; n_; i++) {
            IteratorWrapper* child = &amp;children_[i];
            if (child != current_) {
                child-&gt;Seek(key());
                if (child-&gt;Valid()) {
                    // child&#x4F4D;&#x4E8E;&gt;=key()&#x7684;&#x7B2C;&#x4E00;&#x4E2A;entry&#x4E0A;&#xFF0C;prev&#x79FB;&#x52A8;&#x4E00;&#x4F4D;&#x5230;<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>key()</span>  
                    <span class="token attr-name">child-</span><span class="token punctuation">&gt;</span></span>Prev();
                }
                else { // child&#x6240;&#x6709;&#x7684;entry&#x90FD; &lt; key()&#xFF0C;&#x76F4;&#x63A5;seek&#x5230;last&#x5373;&#x53EF;  
                    child-&gt;SeekToLast();
                }
            }
        }
        direction_ = kReverse;
    }
    //current&#x4E5F;&#x5411;&#x524D;&#x79FB;&#x4E00;&#x4F4D;&#xFF0C;&#x7136;&#x540E;&#x518D;&#x67E5;&#x627E;key&#x6700;&#x5927;&#x7684;Iterator  
    current_-&gt;Prev();
    FindLargest();
}
</code></pre><p>&#x8FD9;&#x5C31;&#x662F;MergingIterator&#x7684;&#x5168;&#x90E8;&#x4EE3;&#x7801;&#x903B;&#x8F91;&#x4E86;&#xFF0C;&#x6BCF;&#x6B21;Next&#x6216;&#x8005;Prev&#x79FB;&#x52A8;&#x65F6;&#xFF0C;&#x90FD;&#x8981;&#x91CD;&#x65B0;&#x904D;&#x5386;&#x6240;&#x6709;&#x7684;&#x5B50;Iterator&#x4EE5;&#x627E;&#x5230;key&#x6700;&#x5C0F;&#x6216;&#x6700;&#x5927;&#x7684;Iterator&#x4F5C;&#x4E3A;current_&#x3002;&#x8FD9;&#x5C31;&#x662F;merge&#x7684;&#x8BED;&#x4E49;&#x6240;&#x5728;&#x4E86;&#x3002;
&#x4F46;&#x662F;&#x5B83;&#x6CA1;&#x6709;&#x8003;&#x8651;&#x5230;&#x5220;&#x9664;&#x6807;&#x8BB0;&#x7B49;&#x95EE;&#x9898;&#xFF0C;&#x56E0;&#x6B64;&#x76F4;&#x63A5;&#x4F7F;&#x7528;MergingIterator&#x662F;&#x4E0D;&#x80FD;&#x6B63;&#x786E;&#x7684;&#x904D;&#x5386;DB&#x7684;&#xFF0C;&#x8FD9;&#x4E9B;&#x95EE;&#x9898;&#x7559;&#x5F85;&#x7ED9;DBIter&#x6765;&#x89E3;&#x51B3;&#x3002;</p>
<footer class="page-footer"><span class="copyright">&#x5982;&#x9700;&#x4E0B;&#x8F7D;&#x672C;&#x7AD9;&#x5168;&#x90E8;&#x6280;&#x672F;&#x6587;&#x7AE0;&#xFF0C;&#x53EF;&#x4EE5;&#x5728;&#x3010;&#x9AD8;&#x6027;&#x80FD;&#x670D;&#x52A1;&#x5668;&#x5F00;&#x53D1;&#x3011;&#x516C;&#x4F17;&#x53F7;&#x56DE;&#x590D;&#x5173;&#x952E;&#x5B57;&#x201C;&#x6587;&#x7AE0;&#x4E0B;&#x8F7D;&#x201D;&#x5373;&#x53EF;&#x3002;</span><span class="footer-modification">&#x6700;&#x8FD1;&#x66F4;&#x65B0;&#x65F6;&#x95F4;&#xFF1A;
2020-10-03 13:51:42
</span></footer>
<script>console.log("plugin-popup....");document.onclick = function(e){ e.target.tagName === "IMG" && window.open(e.target.src,e.target.src)}</script><style>img{cursor:pointer}</style>
						
					</section>
					
    </div>
    <div class="search-results">
        <div class="has-results">
            
            <h1 class="search-results-title"><span class='search-results-count'></span> results matching "<span class='search-query'></span>"</h1>
            <ul class="search-results-list"></ul>
            
        </div>
        <div class="no-results">
            
            <h1 class="search-results-title">No results matching "<span class='search-query'></span>"</h1>
            
        </div>
    </div>
</div>

				</div>
			</div>
			
		</div>

		
		
		<a href="leveldb源码分析20.html" class="navigation navigation-prev " aria-label="Previous page: leveldb源码分析20">
			<i class="fa fa-angle-left"></i>
		</a>
		
		
		<a href="leveldb源码分析22.html" class="navigation navigation-next " aria-label="Next page: leveldb源码分析22">
			<i class="fa fa-angle-right"></i>
		</a>
		
		
		
	</div>
	<script>
		var gitbook = gitbook || [];
		gitbook.push(function() {
			gitbook.page.hasChanged({"page":{"title":"leveldb源码分析21","level":"7.2.21","depth":2,"next":{"title":"leveldb源码分析22","level":"7.2.22","depth":2,"path":"articles/leveldb源码分析/leveldb源码分析22.md","ref":"articles/leveldb源码分析/leveldb源码分析22.md","articles":[]},"previous":{"title":"leveldb源码分析20","level":"7.2.20","depth":2,"path":"articles/leveldb源码分析/leveldb源码分析20.md","ref":"articles/leveldb源码分析/leveldb源码分析20.md","articles":[]},"dir":"ltr"},"config":{"plugins":["chapter-fold","-lunr","-search","search-pro","splitter","popup","back-to-top-button","hide-element","prism","-highlight","tbfed-pagefooter","code","anchor-navigation-ex","theme-fexa","livereload"],"styles":{"website":"styles/website.css","pdf":"styles/pdf.css","epub":"styles/epub.css","mobi":"styles/mobi.css","ebook":"styles/ebook.css","print":"styles/print.css"},"pluginsConfig":{"tbfed-pagefooter":{"copyright":"如需下载本站全部技术文章，可以在【高性能服务器开发】公众号回复关键字“文章下载”即可。","modify_label":"最近更新时间：","modify_format":"YYYY-MM-DD HH:mm:ss"},"chapter-fold":{},"prism":{},"livereload":{},"splitter":{},"search-pro":{},"popup":{},"theme-fexa":{"search-placeholder":"输入关键字搜索","logo":"./logo.png","favicon":"./favicon.ico"},"code":{"copyButtons":true},"hide-element":{"elements":[".gitbook-link"]},"fontsettings":{"theme":"white","family":"sans","size":2},"anchor-navigation-ex":{"showLevel":false,"associatedWithSummary":true,"mode":"float","showGoTop":false,"printLog":false,"multipleH1":true,"float":{"floatIcon":"fa fa-navicon","showLevelIcon":false,"level1Icon":"","level2Icon":"","level3Icon":""},"pageTop":{"showLevelIcon":false,"level1Icon":"","level2Icon":"","level3Icon":""}},"back-to-top-button":{},"sharing":{"facebook":true,"twitter":true,"google":false,"weibo":false,"instapaper":false,"vk":false,"all":["facebook","google","twitter","weibo","instapaper"]},"theme-default":{"styles":{"website":"styles/website.css","pdf":"styles/pdf.css","epub":"styles/epub.css","mobi":"styles/mobi.css","ebook":"styles/ebook.css","print":"styles/print.css"},"showLevel":false}},"theme":"default","author":"easy_coder","pdf":{"pageBreaksBefore":"/","headerTemplate":null,"paperSize":"a4","margin":{"right":62,"left":62,"top":36,"bottom":36},"fontSize":12,"fontFamily":"Arial","footerTemplate":null,"chapterMark":"pagebreak","pageNumbers":false},"structure":{"langs":"LANGS.md","readme":"README.md","glossary":"GLOSSARY.md","summary":"SUMMARY.md"},"isbn":"","variables":{},"title":"高性能服务器开发 技术专栏","links":{},"gitbook":"*","description":"","theme-default":{"showLevel":true},"extension":null},"file":{"path":"articles/leveldb源码分析/leveldb源码分析21.md","mtime":"2020-10-03T05:51:42.834Z","type":"markdown"},"gitbook":{"version":"3.2.3","time":"2020-10-09T15:31:57.905Z"},"basePath":"../..","book":{"language":""}});
		});
	</script>
</div>

        
    <script src="../../gitbook/gitbook.js"></script>
    <script src="../../gitbook/theme.js"></script>
    
        
        <script src="../../gitbook/gitbook-plugin-chapter-fold/chapter-fold.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-search-pro/jquery.mark.min.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-search-pro/search.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-splitter/splitter.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-back-to-top-button/plugin.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-hide-element/plugin.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-code/plugin.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-livereload/plugin.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-sharing/buttons.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-fontsettings/fontsettings.js"></script>
        
    
        
        <script src="../../gitbook/gitbook-plugin-theme-fexa/fexa.js"></script>
        
    

    </body>
</html>

